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Portland Cements
Published in M. Rashad Islam, Civil Engineering Materials, 2020
Soundness of cement is the ability of a hardened cement paste to retain its volume after setting, without the delayed destructive expansion. This destructive expansion is caused by excessive amounts of free lime (CaO) or magnesia (MgO). Most Portland cement specifications limit the magnesia content, and thus the expansion. The typical expansion test places a small specimen of cement paste into an autoclave (a high-pressure steam vessel, shown in Figure 3.4). The autoclave is slowly brought to 2.03 MPa (295 psi) and is then kept at that pressure for 3 hours. The change in the specimen length due to its time in the autoclave is measured and reported as a percentage. ASTM C 150 specifies a maximum autoclave expansion of 0.80% for all types of Portland cement. Other standard test methods used to determine soundness are AASHTO T 107 and ASTM C 151.
Properties and characterization of aggregates
Published in Mark Alexander, Sidney Mindess, Aggregates in Concrete, 2005
Mark Alexander, Sidney Mindess
Although 'Soundness' strictly refers to a physical property of aggregates, it is discussed here because it has relevance for aggregate durability. 'Soundness' is a term broadly defined as the ability of aggregate to resist excessive changes in volume as a result of changes in physical conditions, such as freezing and thawing, thermal changes at temperatures above 0 °C, and alternate wetting and drying. It relates to the physical competence or 'physical durability' of the material which is an important property since lack of such durability can severely compromise performance of concrete containing the aggregate. 'Soundness' should therefore be distinguished from volume changes due to chemical reactions between aggregates and their environment. Aggregates are regarded as unsound when volume changes induced by physical effects result in deterioration of the concrete in the form of surface scaling, pop-outs, and cracking. A typical pop-out due to a coarse slag aggregate particle that exhibited unsoundness due to unhydrated CaO (lime) and MgO (periclase) is shown in Figure 3.26.
Pavement Surface Characteristics
Published in Rajib B. Mallick, Tahar El-Korchi, Pavement Engineering, 2017
Soundness refers to an aggregate’s ability to resist degradation caused by climatic/environmental effects (i.e., wetting and drying, freezing and thawing). Sulfate soundness test (AASHTO T 104, ASTM C 88) has been widely used for assessing soundness of aggregates, with either sodium sulfate or magnesium sulfate.
Effect of recycled flux over mechanical properties of A36 steel in submerged arc welding
Published in International Journal of Sustainable Engineering, 2021
Thirunavukkarasu K, Kavimani V, Gopal P.M.
Each specimen welded with RF20, RF30, RF40 and RF50 flux is subjected to both destructive and non-destructive testing. All testings are performed based on AWS and other proper standards that are appropriate for such test. The specimens were cut from weldment for the standard size with the aid of wire electric discharge machining (WEDM) (Sabzi and Dezfuli 2018a). Application of WEDM for specimen preparation before and after welding helps in avoiding formation of heat-affected zone during specimen preparation, which may affect the properties of weld (Sridhar, Biswas, and Mahanta 2019). The destructive testings are hardness test (B3000H Brinell Hardness Tester, FIE Group), tensile test (FIE-UTE HGFL 40 T Universal Testing Machine) and impact test (FIE – IT 30 Impact Tester), while ultrasonic and radiography are the non-destructive testing conducted. Because, soundness of the weld can be evaluated through mechanical testing of weldments such as Hardness, Tensile and Impact testing in addition to non-destructive tests to find internal defects. Impact test reveals the toughness of weldment, that is, ability to withstand shock loads which is an imperative factor considered for weldment during application. Mechanical testing of weldments is performed five times for each specimen, and average value is calculated for further analysis (Sabzi and Dezfuli 2018b).